Off-loading user equipment from a small cell base station for backhaul management

ABSTRACT

The present disclosure presents a method and an apparatus for off-loading user equipment (UE) from a small cell base station. For example, the method may include identifying a first and a second set of UEs from a plurality of UEs at a small cell base station, prioritizing the first and the second set of UEs, and off-loading one or more UEs from the first or the second set of UEs based at least on the prioritization. As such, off-loading of UEs from a small cell base station may be achieved.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present application for patent claims priority to U.S. ProvisionalApplication No. 61/897,098, filed Oct. 29, 2013, entitled “Apparatus andMethod for Off-Loading User Equipment from a Small Cell,” U.S.Provisional Application No. 61/897,061, filed Oct. 29, 2013, entitled“Backhaul Estimation for Small Cells—Calibration,” U.S. ProvisionalApplication No. 61/897,064, filed Oct. 29, 2013, entitled “BackhaulAware Load Management for Small Cells—Passive Estimation,” U.S.Provisional Application No. 61/897,069, filed Oct. 29, 2013, entitled“Backhaul Estimation for Small Cells—Light Active Estimation,” U.S.Provisional Application No. 61/897,114, filed Oct. 29, 2013, entitled“Method and Apparatus for Backhaul Congestion Estimation Using HeavyActive Probing for Small Cells,” U.S. Provisional Application No.61/933,732, filed Jan. 30, 2014, entitled “Backhaul Management of aSmall Cell” all assigned to the assignee hereof and hereby expresslyincorporated by reference herein.

BACKGROUND

Aspects of the present disclosure relate generally to wirelesscommunication systems, and more particularly to backhaul estimation forsmall cells and the like.

Wireless communication networks are widely deployed to provide variouscommunication services such as telephony, video, data, messaging,broadcasts, and so on. Such networks, which are usually multiple accessnetworks, support communications for multiple users by sharing theavailable network resources. In cellular networks, macro base stations(or macro cells or conventional base stations) provide connectivity andcoverage to a large number of users over a certain geographical area. Tosupplement macro base stations, restricted power or restricted coveragebase stations, referred to as small coverage base stations or small cellbase stations or small cells, can be deployed to provide more robustwireless coverage and capacity to mobile devices. For example, smallcells can be deployed for incremental capacity growth, richer userexperience, in-building or other specific geographic coverage, and/orthe like.

However, the deployment of small cell base stations may also encroach onthe operation of other devices that typically utilize the same space,such as Wireless Local Area Network (WLAN) devices operating inaccordance with one of the IEEE 802.11x communication protocols(so-called “Wi-Fi” devices) or other wired or wireless devices sharingthe same Internet connection in a user's residence or office building.The unmanaged sharing of common backhaul resources may lead to variousthroughput and/or data integrity problems for all devices.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects notdelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

The present disclosure presents an example method and apparatus foroff-loading user equipment (UE) from a small cell base station. Forexample, in an aspect, the present disclosure presents an example methodthat may include identifying a first and a second set of UEs from aplurality of UEs at a small cell base station, prioritizing the firstand the second set of UEs, and off-loading one or more UEs from thefirst or the second set of UEs based at least on the prioritization.

Additionally, the present disclosure presents an example apparatus foroff-loading user equipment (UE) from a small cell base station that mayinclude means for identifying a first and a second set of UEs from aplurality of UEs at a small cell base station, means for prioritizingthe first and the second set of UEs separately, and means foroff-loading one or more UEs from the first or the second set of UEsbased at least on the prioritization.

In a further aspect, the present disclosure presents a non-transitorycomputer readable medium for off-loading user equipment (UE) at a smallcell base station comprising code that, when executed by a processor orprocessing system included within the small cell base station, cause thesmall cell base station to identify a first and a second set of UEs froma plurality of UEs at a small cell base station, prioritize the firstand the second set of UEs separately, and off-load one or more UEs fromthe first or the second set of UEs based at least on the prioritization.

Furthermore, in an aspect, the present disclosure presents an exampleapparatus for off-loading user equipment (UE) from a small cell basestation that may include an identifying component to identify a firstand a second set of UEs from a plurality of UEs at a small cell basestation, a prioritizing component to prioritize the first and the secondset of UEs separately, and an off-loading component to off-load one ormore UEs from the first or the second set of UEs based at least on theprioritization.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative featuresof the one or more aspects. These features are indicative, however, ofbut a few of the various ways in which the principles of various aspectsmay be employed, and this description is intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual diagram of an example of an access network inwhich the present aspects may be implemented;

FIG. 2 is a conceptual diagram of an example communication networkenvironment in which the present aspects may be implemented;

FIG. 3 is a conceptual diagram of another example of a communicationnetwork environment in which the present aspects may be implemented;

FIG. 4 is a flow diagram providing an overview of various aspects ofbackhaul estimation as contemplated by the present disclosure;

FIG. 5 is a flow diagram of an example method for off-loading of UEs inaspects of the present disclosure;

FIG. 6 is an example apparatus in aspects of the present disclosure;

FIG. 7 is a block diagram of an example of a NodeB in communication witha UE in a telecommunications system in which the present aspects may beimplemented; and

FIG. 8 is a block diagram of an example of a small cell apparatus,represented as a series of interrelated functional modules, according toa present aspect.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of various configurations and isnot intended to represent the only configurations in which the conceptsdescribed herein may be practiced. The detailed description includesspecific details for the purpose of providing a thorough understandingof various concepts. However, it will be apparent to those skilled inthe art that these concepts may be practiced without these specificdetails. In some instances, well known structures and components areshown in block diagram form in order to avoid obscuring such concepts.

The present disclosure presents a method and an apparatus foroff-loading user equipment (UE) from a small cell base station. Forexample, the method may include identifying a first and a second set ofUEs from a plurality of UEs at a small cell base station, prioritizingthe first and the second set of UEs, and off-loading one or more UEsfrom the first or the second set of UEs based at least on theprioritization.

As used herein, the term “small cell” may refer to an access point or toa corresponding coverage area of the access point, where the accesspoint in this case has a relatively low transmit power or relativelysmall coverage as compared to, for example, the transmit power orcoverage area of a macro network based station or macro cell. Forinstance, a macro cell may cover a relatively large geographic area,such as, but not limited to, several kilometers in radius. In contrast,a small cell may cover a relatively small geographic area, such as, butnot limited to, a home, a building, or a floor of a building. As such, asmall cell may include, but is not limited to, an apparatus such as abase station (BS), an access point, a femto node, a femtocell, a piconode, a micro node, a wireless relay station, a Node B, evolved Node B(eNB), home Node B (HNB) or home evolved Node B (HeNB). Therefore, theterm “small cell,” as used herein, refers to a relatively low transmitpower and/or a relatively small coverage area cell as compared to amacro cell.

FIG. 1 illustrates an example wireless communication network 100demonstrating multiple access communications, and in which the presentaspects may be implemented. The illustrated wireless communicationnetwork 100 is configured to support communication among a numbers ofusers. As shown, the wireless communication network 100 may be dividedinto one or more cells 102, such as the illustrated cells 102A-102G.Communication coverage in cells 102A-102G may be provided by one or morebase stations 104, such as the illustrated base stations 104A-104G. Inthis way, each base station 104 may provide communication coverage to acorresponding cell 102. The base station 104 may interact with aplurality of user devices 106, such as the illustrated user devices106A-106L.

Each user device 106 may communicate with one or more of the basestations 104 on a downlink (DL) and/or an uplink (UL). In general, a DLis a communication link from a base station to a user device, while anUL is a communication link from a user device to a base station. Thebase stations 104 may be interconnected by appropriate wired or wirelessinterfaces allowing them to communicate with each other and/or othernetwork equipment. Accordingly, each user device 106 may alsocommunicate with another user device 106 through one or more of the basestations 104. For example, the user device 106J may communicate with theuser device 106H in the following manner: the user device 106J maycommunicate with the base station 104D, the base station 104D may thencommunicate with the base station 104B, and the base station 104B maythen communicate with the user device 106H, allowing communication to beestablished between the user device 106J and the user device 106H.

The wireless communication network 100 may provide service over a largegeographic region. For example, the cells 102A-102G may cover a fewblocks within a neighborhood or several square miles in a ruralenvironment. In some systems, each cell may be further divided into oneor more sectors (not shown). In addition, the base stations 104 mayprovide the user devices 106 access within their respective coverageareas to other communication networks, such as the Internet or anothercellular network. Each user device 106 may be a wireless communicationdevice (e.g., a mobile phone, router, personal computer, server, etc.)used by a user to send and/or receive voice and/or data over acommunications network, and may be alternatively referred to as anAccess Terminal (AT), a Mobile Station (MS), a User Equipment (UE), etc.In the example shown in FIG. 1, user devices 106A, 106H, and 106Jcomprise routers, while the user devices 106B-106G, 106I, 106K, and 106Lcomprise mobile phones. Again, however, each of the user devices106A-106L may comprise any suitable communication device.

For their wireless air interfaces, each base station 104 may operateaccording to one of several Radio Access Technologies (RATs) dependingon the network in which it is deployed, and may be alternativelyreferred to as a NodeB, evolved NodeB (eNB), etc. These networks mayinclude, for example, Code Division Multiple Access (CDMA) networks,Time Division Multiple Access (TDMA) networks, Frequency DivisionMultiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks,Single-Carrier FDMA (SC-FDMA) networks, and so on. The terms “network”and “system” are often used interchangeably. A CDMA network mayimplement a RAT such as Universal Terrestrial Radio Access (UTRA),cdma2000, etc. UTRA includes Wideband-CDMA (W-CDMA) and Low Chip Rate(LCR). cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMAnetwork may implement a RAT such as Global System for MobileCommunications (GSM). An OFDMA network may implement a RAT such asEvolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE 802.20,Flash-OFDM®, etc. UTRA, E-UTRA, and GSM are part of Universal MobileTelecommunication System (UMTS). One example of such a network is theUMTS Terrestrial Radio Access Network (UTRAN). The UTRAN is the radioaccess network (RAN) defined as a part of the Universal MobileTelecommunications System (UMTS), a third generation (3G) mobile phonetechnology supported by the 3rd Generation Partnership Project (3GPP).The UMTS, which is the successor to Global System for MobileCommunications (GSM) technologies, currently supports various airinterface standards, such as Wideband-Code Division Multiple Access(W-CDMA), Time Division-Code Division Multiple Access (TD-CDMA), andTime Division-Synchronous Code Division Multiple Access (TD-SCDMA). TheUMTS also supports enhanced 3G data communications protocols, such asHigh Speed Packet Access (HSPA), which provides higher data transferspeeds and capacity to associated UMTS networks.

These multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. An example of an emergingtelecommunication standard is Long Term Evolution (LTE). LTE is a set ofenhancements to the Universal Mobile Telecommunications System (UMTS)mobile standard promulgated by Third Generation Partnership Project(3GPP). It is designed to better support mobile broadband Internetaccess by improving spectral efficiency, lowering costs, improvingservices, making use of new spectrum, and better integrating with otheropen standards using OFDMA on the downlink (DL), SC-FDMA on the uplink(UL), and multiple-input multiple-output (MIMO) antenna technology.However, as the demand for mobile broadband access continues toincrease, there exists a need for further improvements in LTEtechnology. Preferably, these improvements should be applicable to othermulti-access technologies and the telecommunication standards thatemploy these technologies.

Long Term Evolution (LTE) is a release of UMTS that uses E-UTRA. UTRA,

E-UTRA, GSM, UMTS, and LTE are described in documents from anorganization named “3rd Generation Partnership Project” (3GPP). cdma2000is described in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2).

In cellular networks, macro base stations (or macro cells orconventional base stations) provide connectivity and coverage to a largenumber of users over a certain geographical area. A macro cell networkdeployment is carefully planned, designed, and implemented to offer goodcoverage over the geographical region. Even such careful planning,however, cannot fully accommodate channel characteristics such asfading, multipath, shadowing, etc., especially in indoor environments.Indoor users therefore often face coverage issues (e.g., call outagesand quality degradation) resulting in poor user experience. Further,macro cell capacity is upper-bounded by physical and technologicalfactors.

Thus, as discussed above, small cell base stations may be used toprovide significant capacity growth, in-building coverage, and in somecases different services than macro cells operating alone, therebyfacilitating a more robust user experience.

FIG. 2 illustrates an example mixed communication network environment200 in which small cell base stations (or small cells) are deployed inconjunction with macro cell base stations (or macro cells), and in whichthe present aspects may be implemented. As discussed above, small cellbase stations may be used to provide significant capacity growth,in-building coverage, and in some cases different services than macrocells operating alone, thereby facilitating a more robust userexperience.

In FIG. 2, a macro cell base station 205 may provide communicationcoverage to one or more user devices, for example, user equipment 220,221, and 222, within a macro cell coverage area 230 (as discussed abovein more detail with reference to FIG. 1), while small cell base stations210 and 212 may provide their own communication coverage withinrespective small cell coverage areas 215 and 217, with varying degreesof overlap among the different coverage areas. It is noted that certainsmall cells may be restricted in some manner, such as for associationand/or registration, and may therefore be referred to as ClosedSubscriber Group (“CSG”) cells. In this example, at least some userdevices, e.g., user equipment 222, may be capable of operating both inmacro environments (e.g., macro areas) and in smaller scale networkenvironments (e.g., residential, femto areas, pico areas, etc.) asshown.

Turning to the illustrated connections in more detail, user equipment220 may generate and transmit a message via a wireless link to the macrocell base station 205, the message including information related tovarious types of communication (e.g., voice, data, multimedia services,etc.). User equipment 222 may similarly communicate with small cell basestation 210 via a wireless link, and user equipment 221 may similarlycommunicate with small cell base station 212 via a wireless link. Themacro cell base station 205 may also communicate with a correspondingwide area or external network 240 (e.g., the Internet), via a wired linkor via a wireless link, while small cell base stations 210 and/or 212may also similarly communicate with network 240, via their own wired orwireless links. For example, small cell base stations 210 and/or 212 maycommunicate with network 240 by way of an Internet Protocol (IP)connection, such as via a Digital Subscriber Line (DSL, e.g., includingAsymmetric DSL (ADSL), High Data Rate DSL (HDSL), Very High Speed DSL(VDSL), etc.), a TV cable carrying IP traffic, a Broadband over PowerLine (BPL) connection, an Optical Fiber (OF) cable, or some other link.This connection may utilize the existing backhaul infrastructureprovided by, for example, an ISP for the residential home or officebuilding in which small cells 210 and 212 are installed, and mayaccordingly be shared among other devices operating in the sameenvironment, such as Wireless Local Area Network (WLAN) devicesoperating in accordance with one of the IEEE 802.11x communicationprotocols (so-called “Wi-Fi” devices) or other wired or wireless devicessharing the same Internet connection in a user's residence or officebuilding.

The network 240 may comprise any type of electronically connected groupof computers and/or devices, including, for example, the followingnetworks: Internet, Intranet, Local Area Networks (LANs), or Wide AreaNetworks (WANs). In addition, the connectivity to the network may be,for example, by remote modem, Ethernet (IEEE 802.3), Token Ring (IEEE802.5), Fiber Distributed Datalink Interface (FDDI) AsynchronousTransfer Mode (ATM), Wireless Ethernet (IEEE 802.11), Bluetooth (IEEE802.15.1), or some other connection. As used herein, the network 240includes network variations such as the public Internet, a privatenetwork within the Internet, a secure network within the Internet, aprivate network, a public network, a value-added network, an intranet,and the like. In certain systems, the network 240 may also comprise aVirtual Private Network (VPN).

Accordingly, it will be appreciated that macro cell base station 205and/or either or both of small cell base stations 210 and 212 may beconnected to network 240 using any of a multitude of devices or methods.These connections may be referred to as the “backbone” or the “backhaul”of the network, and may in some implementations be used to manage andcoordinate communications between macro cell base station 205, smallcell base station 210, and/or small cell base station 212. In this way,depending on the current location of user equipment 222, for example,user equipment 222 may access the communication network 240 by macrocell base station 205 or by small cell base station 210.

FIG. 3 illustrates an example communication system 300 in which a smallcell base station shares a backhaul connection with other wired and/orwireless devices, and in which the present aspects may be implemented.For example, a home router 302 is installed in a user residence 304 andprovides access to the Internet 306 via an Internet service provider(ISP) 308. The home router 302 communicates (e.g., transfers user dataand other signaling information) with ISP 308 via a modem 315 over acorresponding backhaul link 310. In an aspect, for example, the homerouter 302 may support various wired and/or wireless devices, such as ahome computer 312, a wireless fidelity (Wi-Fi) enabled TV 314, etc. Inan additional aspect, the home router 302 may include a wireless accesspoint (AP), for example, a Wi-Fi access point (AP) providingconnectivity to such devices. In an additional aspect, for example, thehome router 302 may be integrated with a wireless access point Wi-Fi APfor providing connectivity to such devices.

In an aspect, a small cell base station (or a small cell) 320 isinstalled in user residence 304 and serves one or more nearby userequipments (UE) 322 as described above. The small cell base station 320via its connection to home router 302 and shared backhaul link 310 mayprovide access to Internet 306 and core network 316. Since the backhaullink 310 is shared between the traffic managed by small cell 320 (e.g.,native traffic) and traffic generated by other devices that home router302 may be serving (e.g., cross traffic), there is a potential forcongestion of uplink (UL) traffic, down link (DL) traffic, and/or both,with varying degrees of impact on the performance of the small celland/or other devices sharing the backhaul link 310.

In an aspect, small cell base station 320 may be configured to include abackhaul-aware load management (BALM) component 324 operable to mitigatecongestion on backhaul link 310. The operation of BALM component 324 mayenable small cell base station 320 to determine various backhaulcharacteristics, for example, sustainable throughput, and correspondingdelay and jitter variations, loss, etc., to identify backhaul congestionand/or take appropriate remedial actions. For example, in an aspect,when congestion is present, operation of BALM component 324 may enablesmall cell base station 320 via its radio resource management (RRM)module to offload one or more UEs 322 to a macro cell base station orotherwise reduce the coverage area of small cell base station 320 inorder to reduce the number of UEs 322 being served. In an additionalaspect, when congestion is present, operation of BALM component 324 mayenable small cell base station 320 via its RRM module to offload one ormore low throughput devices to a macro cell base station and/or reducethe coverage area of small cell base station 320 by lowering a pilotchannel signal strength in order to reduce the number of UEs 322 beingserved. In an additional or optional aspect, operation of BALM component324 may enable small cell base station 320 to limit the data rate ofcertain flows that are not backhaul-limited (e.g., by changing a videoencoding rate). In a further additional or optional aspect, operation ofBALM component 324 may enable small cell base station 320 to alert theuser of one of the UEs 322 to enable the user of the UE to choose one ofthe above-noted actions and control the operation of the small cell. Inan additional or optional aspect, the user of the UE may be alerted viaa graphical user interface (GUI) to allow the user of the UE to chooseone of the above-noted actions as described above.

FIG. 4 is a flow diagram 400 providing an overview of various BALMrelated procedures performed by a small cell base station via operationof BALM component 324. For example, in an aspect, a small cell basestation (e.g., small cell base station 320 of FIG. 3) via operation ofBALM component 324 may continually or periodically monitor throughputconditions of UEs supported (e.g., camped) by the small cell basestation to determine if the throughput at the UE is sufficient orotherwise acceptable (e.g., naturally low-rate traffic, Internet peerlimited, etc.). If the small cell base station via operation of BALMcomponent 324 detects that the throughput appears to be insufficientand/or unacceptable, then the small cell base station via operation ofBALM component 324 may then determine whether the underlying congestionis backhaul related, air link related, located in the UE's peer, and/orsimply due to a low-rate application, and may take an appropriateaction. For example, in an aspect, the determination may be based onwhether the backhaul has unused capacity. If the small cell base stationvia operation of BALM component 324 detects that the backhaul has unusedcapacity, the backhaul may generally have no impact on the UEexperiencing a low-throughput condition.

Referring in more detail to FIG. 4, in an aspect, for each UE (e.g.,each of the UEs 322 in FIG. 3), a small cell base station (e.g., smallcell base station 320 in FIG. 3) via operation of BALM component 324 mayperform a light passive estimation procedure to determine if theexisting throughput is sufficient for the UE (decision 402). Forexample, the determination may be made for both for the UL, DL, and/orboth, either separately or together. If the existing throughput issufficient (‘yes’ at decision 402), there is no congestion problem forthe UE and the small cell base station continues to perform lightpassive estimation monitoring as appropriate, as described above.

In an aspect, if it is determined that the existing throughput is notsufficient (‘no’ at decision 402), the small cell base station viaoperation of BALM component 324 checks whether it is over-the-air (OTA)capacity that is limiting the throughput (decision 404). If it isdetermined that the OTA capacity is limiting the throughput (‘yes’ atdecision 404), the small cell base station via operation of BALMcomponent 324 may take remedial actions to relieve the congestion on itsair link, e.g., marking the UE as a candidate for handout to, e.g., amacro cell base station (block 406). In an alternate aspect, if it isdetermined that it is not the OTA capacity that is limiting thethroughput (‘no’ at decision 404), the small cell base station viaoperation of BALM component 324 may perform a per-user rate shapingprocedure and determine if other UEs being served by the small cell basestation are limiting backhaul throughput (decision 408). In anadditional aspect, if it is determined that other UEs being served bythe small cell base station are limiting the backhaul throughput (‘yes’at decision 408), the small cell base station via operation of BALMcomponent 324 may take remedial actions, e.g., marking the userequipment as a candidate for handout to a macro cell base station (block406).

In an aspect, if it is determined that the other UEs being served by thesmall cell base station are not limiting the backhaul throughput (‘no’at decision 408), the small cell base station via operation of BALMcomponent 324 may perform a light active estimation procedure (forexample, estimation of backhaul state using actively-induced packetswith small overhead or naturally-induced/occurring packets whosestatistical characteristics make them a good replacement foractively-induced packets for light active estimation, which aretypically used to directly measure backhaul latency and loss) todetermine if the Internet service provider (ISP) queue is fully utilized(decision 410). If it is determined that the ISP queue does not appearto be full (‘no’ at decision 410), there may be no backhaul capacityproblem and the small cell base station via operation of BALM component324 may revert to performing light passive estimation monitoring asappropriate, as described above. In an alternative aspect, if it isdetermined that the ISP queue does appear to be full (‘yes’ at decision410), there may be a backhaul capacity problem and the small cell basestation via operation of BALM component 324 may further perform a heavyactive estimation procedure (e.g., estimation of backhaul state usingactively-induced packets with potentially high overhead, ornaturally-induced/occurring packets whose statistical characteristicsmake them a good replacement for actively-induced packets for heavyactive estimation, which are typically used to directly measurethroughput) to determine if the throughput is being limited bycongestion at the Internet peer with which the UE is communicating,rather than by the backhaul link itself (decision 412).

In an aspect, if it is determined that throughput is not being limitedby congestion at the Internet peer with which the UE is communicating(‘no’ at decision 412), the small cell base station via operation ofBALM component 324 may determine that there is a backhaul capacityproblem and may take remedial actions, e.g., marking the UE as acandidate for handout to a macro cell base station (block 406). In analternative aspect, if it is determined that the throughput is beinglimited by congestion at the Internet peer with which the UE iscommunicating (‘no’ at decision 412), there may be no backhaul capacityproblem and the small cell base station via operation of BALM component324 may revert to performing light passive estimation monitoring asappropriate, as described above.

In an aspect, in order to optimize BALM component 324 and the differentBALM related procedures in FIG. 4, the small cell base station viaoperation of BALM component 324 may perform various calibrationprocedures on a continual, periodic, and/or or an event-driven basis.For example, different backhaul networks may experience congestiondifferently, e.g., at least in part due to the different subscriptionpolicies and schedulers used by the different ISPs to implement theirrespective networks. Additionally, small cell base stations aretypically blind to the particular ISP implementations andpre-configurations to accommodate all potential variations would beexhaustive if not prohibitive. Accordingly, a small cell base stationoperating BALM component 324 configured to perform BALM relatedprocedures as described above may be further configured to calibrate theprocedures by determining, e.g., in an automated manner, variousparameters related to the backhaul implementation (“backhaulparameters”) in which the small cell base station is deployed.

FIG. 5 is a flow diagram 500 illustrating an example method used in anaspect of off-loading user equipment (UE) from a small cell base stationfor backhaul management at a small cell base station.

In an aspect, at block 510, methodology 500 may include identifying afirst and a second set of UEs from a plurality of UEs at a small cellbase station. For example, in an aspect, small cell base station 320and/or BALM component 324 may include a specially programmed processormodule, or a processor executing specially programmed code stored in amemory, to identify a first and a second set of UEs from a plurality ofUEs at a small cell base station.

For example, in an aspect, BALM component 324 may be configured toidentify a first set and a second set of UEs from a plurality of UEs atsmall cell base station 320. In an aspect, the small cell base stationmay be a serving cell for the plurality of UEs or the plurality of UEscan be camped on the small cell base station. In an aspect, for example,BALM component 324 may identify UEs that are “unsatisfied” as a firstset and/or UEs that are “satisfied” as a second set from the pluralityof UEs.

For example, in an aspect, a UE may be identified as unsatisfied if theperformance of the UE, e.g., average throughout of the UE, when campedon the base station, is limited or restricted due to the backhaul (e.g.,limited in capacity and/or quality) of the small cell base station. A UEmay be identified as satisfied if the performance of the UE, e.g.,average throughout of the UE, when camped on the base station, is notlimited or restricted due to the backhaul (e.g., limited in capacityand/or quality) of the small cell base station. In an aspect, BALMcomponent 324 may identify UEs as unsatisfied or satisfied based onpassive estimation technique as described above. In an additional oroptional aspect, BALM component 324 may identify UEs as unsatisfied orsatisfied further based on other estimation techniques as describedabove, for example, light active estimation and/or heavy activeestimation.

In an aspect, BALM component 324 may be configured to detect full queueutilization via light active estimation. For example, as described inblock 410 of FIG. 4, BALM component 324 may be configured to detect fullqueue utilization in the direction of interest, e.g., downlink, uplink,or both. In an additional aspect, during active estimation, for example,blocks 410 or 412 of FIG. 4, BALM component 324 may determine whether aUE could achieve better bandwidth. If it is determined that the UE couldachieve better bandwidth, the passive throughout threshold that may besatisfied may be temporarily dropped for this UE to match the observedthroughput when the UE was identified as satisfied.

In an additional aspect, BALM component 324 may have active estimationruns configured to determine whether passive estimation findings remainvalid over a pre-defined amount of time, e.g., “x” minutes. In anadditional aspect, BALM component 324 may reset passive estimationfindings if the UE is determined to use a new flow, e.g., fromtransition through low slot utilization. These procedures may improvethe reliability of passive estimation findings.

In an aspect, at block 520, methodology 500 may include prioritizing thefirst and the second set of UEs, for the purposes of addressing backhaullimitation. For example, in an aspect, small cell base station 320and/or BALM component 324 may include a specially programmed processormodule, or a processor executing specially programmed code stored in amemory, to prioritize the first and the second set of UEs.

In an aspect, BALM component 324 may be configured to prioritize thefirst set over the second set of UEs. For example, in an aspect, BALMcomponent 324 may be configured to prioritize the set of UEs that areidentified as unsatisfied (e.g., first set) and/or the set of UE thatare identified as satisfied (e.g., second set). In an additional aspect,for example, the unsatisfied UEs may be prioritized in an increasingorder of average throughout and/or the satisfied UEs may be prioritizedin a decreasing order of average throughput. In an further additionalaspect, if both traffic directions are determined as unsatisfied, thethroughout in any one direction may be used, or weighed summation ofthroughputs in both directions (e.g., on a per UE basis) may be used.

In an additional or optional aspect, BALM component 324 may beconfigured to lower the off-load priority of the UEs identified above.For example, in an aspect, the UE whose priority is to be reduced may bemoved to be the last item in the list, e.g., last in the entire list, orlast in the sub-list of unsatisfied or satisfied UEs. In a furtheradditional or optional aspect, weights may be assigned to the UEsthroughout to affect their priority, e.g., where priority is determinedbased on sorting average throughout. For example, unsatisfied member UEsmay be assigned a higher weight or a constant value can be added.Alternatively or additionally, satisfied UEs may be assigned lowerweights or a constant value can be subtracted.

In an aspect, at block 530, methodology 500 may include off-loading oneor more UEs from the first or the second set of UEs based at least onthe prioritization. For example, in an aspect, small cell base station320 and/or BALM component 324 may include a specially programmedprocessor module, or a processor executing specially programmed codestored in a memory, to off-load one or more UEs from the first or thesecond set of UEs based at least on the prioritization. For example, inan aspect, BALM component 324 can off-load one or more unsatisfiedand/or satisfied UEs from the small cell base station to a macro cellbase station or another small cell base station.

In an aspect, for example, BALM component 324, e.g., radio resourcemanagement (RRC) layer of small cell base station 320, may off-load oneor more UEs from the small cell base station in the order of priority,where the order of priority is determined as described above. Forexample, in an aspect, a single UE may be off-loaded to improveperformance of the other UEs on the small cell base station. In anadditional or optional aspect, multiple UEs may be off-loaded when BALMcomponent 324 determines that off-loading of a single UE from the smallcell base station would not sufficiently help the remaining UEs on thesmall cell base station.

In an additional aspect, a priority list of UE sets (e.g., sets of UEs)may be determined for off-loading from the small cell base station. Forexample, in an aspect, higher priority may be given to a UE set with aminimum number of UEs to off-load. In a further additional aspect, a UEset whose off-load leaves relatively higher throughput for the remainingUEs on the small cell base station may be given higher priority.Additionally, in an aspect, a UE set whose off-load leaves relativelyhigher number of satisfied UEs on the small cell base station may bealso given higher priority.

In an additional or optional aspect, BALM component 324 may assign ahigher priority to a UE set whose off-load leaves most throughput forthe remaining UEs on the small cell base station (or whose off-loadleaves UEs that may be satisfied on the small cell base station). In anaspect, BALM component 324 may off-load UEs in a given set when all UEsare designated for potential off-load. Otherwise, BALM component 324 mayattempt to off-load the UEs in the given set in the next set.

In an aspect, BALM component 324 may check the UEs in the set to beoff-loaded are present in the coverage area of at least another cell sothat they can be successfully offloaded to another small cell basestation or a macro cell base station. If one of the UEs cannot be handedout (e.g., another cell is not available for a handout), then another UEmay be picked for off-loading.

In an aspect, when BALM component 324 identifies a UE as unsatisfied viapassive estimation, BALM component 324 may off-load the UE to anotherbase station. For example, the other base station may be another smallcell base station or a macro cell base station. In an additional oroptional aspect, BALM component 324 may perform an additional check toensure the previous estimate of UE satisfaction status is notinvalidated by a later active estimation run. For example, the activeestimation may be light active estimation or heavy active estimation.

FIG. 6 illustrates an aspect of the configuration of BALM component 324in an example small cell base station 600 for off-loading user equipment(UE) from a small cell base station. In this example, small cell basestation 600 is deployed in the vicinity of one or more client devices640, such as the UEs 322 in FIG. 3, and a router 630 providing Internetaccess, such as the home router 302 in FIG. 3. It should be noted thatBALM component 324 may include all or some portion of the following, ormay include a separate portion of some of these components that are incommunication with remaining ones of these components.

In general, the small cell base station 600 and/or BALM component 324includes various components for providing and processing services forthe client devices 640. For example, the small cell base station 600 mayinclude a transceiver 612 for wireless communication with the one ormore of the clients 640 and a backhaul controller 614 for backhaulcommunications with other network devices, such as the router 630. Thesecomponents may operate under the direction of a processor 616 inconjunction with memory 618, for example, all of which may beinterconnected via a bus 620 or the like.

In addition and in accordance with the discussion above, the small cellbase station 600 (similar to small cell base station 320) and/or BALMcomponent 324 may also further include an identifying component 622 foridentifying a first and a second set of UEs from a plurality of UEs atsmall cell base station 320, a prioritizing component to prioritize 624the first set and the second set of UEs, and/or an off-loading component626 for off-loading one or more UEs from the first or the second set ofUEs based at least on the prioritization.

It will be appreciated that in some designs one or more or all of theseoperations may be performed by or in conjunction with the processor 616and memory 618.

FIG. 7 illustrates in more detail the principles of wirelesscommunication between a wireless device 710 (e.g., small cell basestation 320 of FIG. 3), including BALM component 324, and a wirelessdevice 750 (e.g., UE 322 of FIG. 3) of a sample communication system 700that may be adapted as described herein. In an aspect, the functionalityof BALM component 324 may be in one or more modules or instructionswithin processor 730, or within computer readable instructions stored inmemory 732 and executable by processor 730, or some combination of both.

At the device 710, traffic data for a number of data streams is providedfrom a data source 712 to a transmit (TX) data processor 714. Each datastream may then be transmitted over a respective transmit antenna.

The TX data processor 714 formats, codes, and interleaves the trafficdata for each data stream based on a particular coding scheme selectedfor that data stream to provide coded data. The coded data for each datastream may be multiplexed with pilot data using OFDM techniques. Thepilot data is typically a known data pattern that is processed in aknown manner and may be used at the receiver system to estimate thechannel response. The multiplexed pilot and coded data for each datastream is then modulated (i.e., symbol mapped) based on a particularmodulation scheme (e.g., BPSK, QSPK, M-PSK, or M-QAM) selected for thatdata stream to provide modulation symbols. The data rate, coding, andmodulation for each data stream may be determined by instructionsperformed by a processor 730. A data memory 732 may store program code,data, and other information used by the processor 730 or othercomponents of the device 710.

The modulation symbols for all data streams are then provided to a TXMIMO processor 720, which may further process the modulation symbols(e.g., for OFDM). The TX MIMO processor 720 then provides NT modulationsymbol streams to NT transceivers (XCVR) 722A through 722T. In someaspects, the TX MIMO processor 720 applies beam-forming weights to thesymbols of the data streams and to the antenna from which the symbol isbeing transmitted.

Each transceiver 722 receives and processes a respective symbol streamto provide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel. NTmodulated signals from transceivers 722A through 722T are thentransmitted from NT antennas 724A through 724T, respectively.

At the device 750, the transmitted modulated signals are received by NRantennas 752A through 752R and the received signal from each antenna 752is provided to a respective transceiver (XCVR) 754A through 754R. Eachtransceiver 754 conditions (e.g., filters, amplifies, and down converts)a respective received signal, digitizes the conditioned signal toprovide samples, and further processes the samples to provide acorresponding “received” symbol stream.

A receive (RX) data processor 760 then receives and processes the NRreceived symbol streams from NR transceivers 754 based on a particularreceiver processing technique to provide NT “detected” symbol streams.The RX data processor 760 then demodulates, deinterleaves, and decodeseach detected symbol stream to recover the traffic data for the datastream. The processing by the RX data processor 760 is complementary tothat performed by the TX MIMO processor 720 and the TX data processor714 at the device 710.

A processor 770 periodically determines which pre-coding matrix to use(discussed below). The processor 770 formulates a reverse link messagecomprising a matrix index portion and a rank value portion. A datamemory 772 may store program code, data, and other information used bythe processor 770 or other components of the device 750.

The reverse link message may comprise various types of informationregarding the communication link and/or the received data stream. Thereverse link message is then processed by a TX data processor 738, whichalso receives traffic data for a number of data streams from a datasource 736, modulated by a modulator 780, conditioned by thetransceivers 754A through 754R, and transmitted back to the device 710.

At the device 710, the modulated signals from the device 750 arereceived by the antennas 724, conditioned by the transceivers 722,demodulated by a demodulator (DEMOD) 740, and processed by a RX dataprocessor 742 to extract the reverse link message transmitted by thedevice 750. The processor 730 then determines which pre-coding matrix touse for determining the beam-forming weights then processes theextracted message.

FIG. 7 also illustrates that the communication components may includeone or more components that perform calibration for management of abackhaul link to an ISP as taught herein. For example, a communication(COMM.) component 790 may cooperate with the processor 730 and/or othercomponents of the device 710 to perform the calibration as taughtherein. Similarly, a communication control component 792 may cooperatewith the processor 770 and/or other components of the device 750 tosupport the configuration as taught herein. It should be appreciatedthat for each device 710 and 750 the functionality of two or more of thedescribed components may be provided by a single component. For example,a single processing component may provide the functionality of thecommunication control component 790 and the processor 730 and a singleprocessing component may provide the functionality of the communicationcontrol component 792 and the processor 770.

FIG. 8 illustrates an example small cell apparatus 800, including BALMcomponent 324, represented as a series of interrelated functionalmodules. In an aspect, small cell apparatus 800 (same as small cell basestation 320) and/or BALM component 324 may include a module foridentifying 802 that may correspond at least in some aspects to, forexample, identifying component 622 as discussed herein, a module forprioritizing 804 that may correspond at least in some aspects to, forexample, prioritizing component 624 as discussed herein, and/or a modulefor off-loading 806 that may correspond at least in some aspects to, forexample, off-loading component 626 as discussed herein.

The functionality of the modules of FIG. 8 may be implemented in variousways consistent with the teachings herein. In some aspects, thefunctionality of these modules may be implemented as one or moreelectrical components. In some aspects, the functionality of theseblocks may be implemented as a processing system including one or moreprocessor components. In some aspects, the functionality of thesemodules may be implemented using, for example, at least a portion of oneor more integrated circuits (e.g., an ASIC). As discussed herein, anintegrated circuit may include a processor, software, other relatedcomponents, or some combination thereof. Thus, the functionality ofdifferent modules may be implemented, for example, as different subsetsof an integrated circuit, as different subsets of a set of softwaremodules, or a combination thereof. Also, it should be appreciated that agiven subset (e.g., of an integrated circuit and/or of a set of softwaremodules) may provide at least a portion of the functionality for morethan one module.

In addition, the components and functions represented by FIG. 8 as wellas other components and functions described herein, may be implementedusing any suitable means. Such means also may be implemented, at leastin part, using corresponding structure as taught herein. For example,the components described above in conjunction with the “module for”components of FIG. 8 also may correspond to similarly designated “meansfor” functionality. Thus, in some aspects one or more of such means maybe implemented using one or more of processor components, integratedcircuits, or other suitable structure as taught herein.

In some aspects, an apparatus or any component of an apparatus may beconfigured to (or operable to or adapted to) provide functionality astaught herein. This may be achieved, for example: by manufacturing(e.g., fabricating) the apparatus or component so that it will providethe functionality; by programming the apparatus or component so that itwill provide the functionality; or through the use of some othersuitable implementation technique. As one example, an integrated circuitmay be fabricated to provide the requisite functionality. As anotherexample, an integrated circuit may be fabricated to support therequisite functionality and then configured (e.g., via programming) toprovide the requisite functionality. As yet another example, a processorcircuit may execute code to provide the requisite functionality.

Those of skill in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof

Further, those of skill in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted as causing adeparture from the scope of the present invention.

The methods, sequences and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of storage medium known in the art. Anexemplary storage medium is coupled to the processor such that theprocessor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor.

Accordingly, an aspect disclosed can include a computer readable mediaembodying a method for calibrating a small cell base station formanagement of a backhaul link to an ISP. Accordingly, the invention isnot limited to illustrated examples and any means for performing thefunctionality described herein are included in aspects disclosed.

While the foregoing disclosure shows illustrative aspects disclosed, itshould be noted that various changes and modifications could be madeherein without departing from the scope of the invention as defined bythe appended claims. The functions, steps and/or actions of the methodclaims in accordance with the aspects described herein need not beperformed in any particular order. Furthermore, although elementsdisclosed may be described or claimed in the singular, the plural iscontemplated unless limitation to the singular is explicitly stated.

In accordance with various aspects of the disclosure, an element, or anyportion of an element, or any combination of elements may be implementedwith a “processing system” that includes one or more processors.Examples of processors include microprocessors, microcontrollers,digital signal processors (DSPs), field programmable gate arrays(FPGAs), programmable logic devices (PLDs), state machines, gated logic,discrete hardware circuits, and other suitable hardware configured toperform the various functionality described throughout this disclosure.One or more processors in the processing system may execute software.Software shall be construed broadly to mean instructions, instructionsets, code, code segments, program code, programs, subprograms, softwaremodules, applications, software applications, software packages,routines, subroutines, objects, executables, threads of execution,procedures, functions, etc., whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise. Thesoftware may reside on a computer-readable medium. The computer-readablemedium may be a non-transitory computer-readable medium. Anon-transitory computer-readable medium includes, by way of example, amagnetic storage device (e.g., hard disk, floppy disk, magnetic strip),an optical disk (e.g., compact disk (CD), digital versatile disk (DVD)),a smart card, a flash memory device (e.g., card, stick, key drive),random access memory (RAM), read only memory (ROM), programmable ROM(PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), aregister, a removable disk, and any other suitable medium for storingsoftware and/or instructions that may be accessed and read by acomputer.

The computer-readable medium may also include, by way of example, acarrier wave, a transmission line, and any other suitable medium fortransmitting software and/or instructions that may be accessed and readby a computer. The computer-readable medium may be resident in theprocessing system, external to the processing system, or distributedacross multiple entities including the processing system. Thecomputer-readable medium may be embodied in a computer-program product.By way of example, a computer-program product may include acomputer-readable medium in packaging materials. Those skilled in theart will recognize how best to implement the described functionalitypresented throughout this disclosure depending on the particularapplication and the overall design constraints imposed on the overallsystem.

It is to be understood that the specific order or hierarchy of steps inthe methods disclosed is an illustration of exemplary processes. Basedupon design preferences, it is understood that the specific order orhierarchy of steps in the methods may be rearranged. The accompanyingmethod claims present elements of the various steps in a sample order,and are not meant to be limited to the specific order or hierarchypresented unless specifically recited therein.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language of the claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” Unless specifically statedotherwise, the term “some” refers to one or more. A phrase referring to“at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: a, b,or c” is intended to cover: a; b; c; a and b; a and c; b and c; and a, band c. All structural and functional equivalents to the elements of thevarious aspects described throughout this disclosure that are known orlater come to be known to those of ordinary skill in the art areexpressly incorporated herein by reference and are intended to beencompassed by the claims. Moreover, nothing disclosed herein isintended to be dedicated to the public regardless of whether suchdisclosure is explicitly recited in the claims. No claim element is tobe construed under the provisions of 35 U.S.C. §112, sixth paragraph,unless the element is expressly recited using the phrase “means for” or,in the case of a method claim, the element is recited using the phrase“step for.”

What is claimed is:
 1. A method for off-loading user equipment (UE) froma small cell base station, comprising: identifying a first and a secondset of UEs from a plurality of UEs at a small cell base station;prioritizing the first and the second set of UEs; and off-loading one ormore UEs from the first or the second set of UEs based at least on theprioritization.
 2. The method of claim 1, wherein the first set of UEsincludes UEs that are identified as unsatisfied at the small cell basestation.
 3. The method of claim 2, wherein the first set of UEs isprioritized in an increasing order of average throughput.
 4. The methodof claim 1, wherein the second set of UEs includes UEs that areidentified as satisfied at the small cell base station.
 5. The method ofclaim 4, wherein the UEs in the second list is prioritized in adecreasing order of average throughput.
 6. The method of claim 1,wherein the off-loading further comprises: off-loading the one or moreUEs from the first or the second set to a macro cell base station oranother small cell base station.
 7. The method of claim 1, wherein theoff-loading further comprises: determining one or more prioritized setsof UEs for off-loading; and off-loading the one or more prioritized setsof UEs based on a pre-determined criterion.
 8. An apparatus foroff-loading user equipment (UE) from a small cell base station,comprising: means for identifying a first and a second set of UEs from aplurality of UEs at a small cell base station; means for prioritizingthe first and the second set of UEs; and means for off-loading one ormore UEs from the first or the second set of UEs based at least on theprioritization.
 9. The apparatus of claim 8, wherein the first set ofUEs includes UEs that are identified as unsatisfied at the small cellbase station.
 10. The apparatus of claim 9, wherein the first set of UEsis prioritized in an increasing order of average throughput.
 11. Theapparatus of claim 8, wherein the second set of UEs includes UEs thatare identified as satisfied at the small cell base station.
 12. Theapparatus of claim 11, wherein the UEs in the second list is prioritizedin a decreasing order of average throughput.
 13. The apparatus of claim8, wherein the off-loading further comprises: means for off-loading theone or more UEs from the first or the second set to a macro cell basestation or another small cell base station.
 14. The apparatus of claim8, wherein the off-loading further comprises: means for determining oneor more prioritized sets of UEs for off-loading; and means foroff-loading the one or more prioritized sets of UEs based on apre-determined criterion.
 15. A non-transitory computer readable mediumfor off-loading user equipment (UE) at a small cell base stationcomprising code that, when executed by a processor or processing systemincluded within the small cell base station, cause the small cell basestation to: identify a first and a second set of UEs from a plurality ofUEs at a small cell base station; prioritize the first and the secondset of UEs; and off-load one or more UEs from the first or the secondset of UEs based at least on the prioritization.
 16. The computerreadable medium of claim 15, wherein the first set of UEs includes UEsthat are identified as unsatisfied at the small cell base station. 17.The computer readable medium of claim 16, wherein the first set of UEsis prioritized in an increasing order of average throughput.
 18. Thecomputer readable medium of claim 15, wherein the second set of UEsincludes UEs that are identified as satisfied at the small cell basestation.
 19. The computer readable medium of claim 18, wherein the UEsin the second list is prioritized in a decreasing order of averagethroughput.
 20. The computer readable medium of claim 15, wherein theoff-loading further comprises: code for off-loading the one or more UEsfrom the first or the second set to a macro cell base station or anothersmall cell base station.
 21. The computer readable medium of claim 15,wherein the off-loading further comprises: code for determining one ormore prioritized sets of UEs for off-loading; and code for off-loadingthe one or more prioritized sets of UEs based on a pre-determinedcriterion.
 22. An apparatus for off-loading user equipment (UE) from asmall cell base station, comprising: an identifying component toidentify a first and a second set of UEs from a plurality of UEs at asmall cell base station; a prioritizing component to prioritize thefirst and the second set of UEs; and an off-loading component tooff-load one or more UEs from the first or the second set of UEs basedat least on the prioritization.
 23. The apparatus of claim 22, whereinthe first set of UEs includes UEs that are identified as unsatisfied atthe small cell base station.
 24. The apparatus of claim 23, wherein thefirst set of UEs is prioritized in an increasing order of averagethroughput.
 25. The apparatus of claim 22, wherein the second set of UEsincludes UEs that are identified as satisfied at the small cell basestation.
 26. The apparatus of claim 25, wherein the UEs in the secondlist is prioritized in a decreasing order of average throughput.
 27. Theapparatus of claim 22, wherein the off-loading component is furtherconfigured to: off-load the one or more UEs from the first or the secondset to a macro cell base station or another small cell base station. 28.The apparatus of claim 22, wherein the off-loading component is furtherconfigured to: determine one or more prioritized sets of UEs foroff-loading; and off-load the one or more prioritized sets of UEs basedon a pre-determined criterion.